铝热-离心法制备TiC/FeNiCr复合材料的抗高温磨损耐腐蚀性能

Wear and Oxidation Resistant Properties of TiC/FeNiCr Composite Coating Produced by Centrifugal-Thermite Process at High Temperature

用铝热-离心工艺在无缝钢管内表面制备了TiC/FeNiCr金属陶瓷涂层,利用X射线衍射、能谱分析仪、扫描电子显微镜等手段研究了涂层的显微结构和组织形貌,在1000℃下选用CrNiMo钢作为对比材料,测试了涂层的抗高温磨损性能和抗氧化性能。结果表明,TiC/FeNiCr涂层由α-FeNiCr、γ-FeNiCr、TiC及NiAl4种相组成,涂层组织细小致密,无粗大枝晶,没有微裂纹;涂层具有优良的抗高温氧化性能,在1000℃下氧化100h后增重小于1mg/cm2,比CrNiMo钢的抗氧化性能提高了120多倍;涂层还具有优异的抗高温磨损性能,在1000℃高温下的体积磨损率大约是CrNiMo钢的1/7。

TiC/FeNiCr cermet composite coating has been prepared in a carbon steel pipe by centrifugal-thermite process. The microstructure of coating has been investigated using X-ray diffraction （XRD） and scanning electron microscope （SEM） attached with EDX. The wear and oxidation resistant properties of coating at 1000 ℃ are measured and compared with CrNiMo steel. Results show that the TiC/FeNiCr composite is composed of α-FeNiCr, γ-FeNiCr, TiC and NiAl. The microstructure of coating is thin and compact, having no large dendritical crystals, microcracks and micropores. The coating has good oxidation resistant property, the mass gain of TiC/FeNiCr layer oxidized at 1000 ℃ for 24 h is lower than l mg/cm2, decreases for 120 times compared with the CrNiMo steel. Also the coating has good high-temperature wear resistant property, the volume wear rate of TiC/FeNiCr is nearly the seventh of the volume wear rater of steel.